Reversing valve



H. E. GUZMAN REVERS ING VALVE Feb. 17, 1970 2 Sheets-Sheet l Filed May 22, 1967 mm F A mm 4 mm 4 Du o /%w T. m a u H. E. GUZMAN REVERSING VALVE Feb. 17, 1970 2 Sheets-Sheet 2 Filed May 22, 1967 INVENTOR. E. GUZMAN Q. %743 M HECTQR .ATTDRUENS United States Patent Office ,7, ,970

3,495,614 REVERSING VALVE Hector E. Guzman, Toledo, Ohio, assigor to Owens- Illinois, Inc., a Corporation of Ohio Filed May 22, 1967, Ser. No. 640,197 Int. Cl. F27d 17/00; F16k 11/10, 51/00 U.S. Cl. 137-311 6 Claims ABSTRACT OF THE DISCLOSURE A valvng apparatus for reversing the flow of combuston air and waste gases in a regenerative type glass furnace, the apparatus including: a stationary bicompartmental hood having two openings to each compartment; two coaxially coupled, counter-rotatable ducts positioned on the hood, each having a single lateral aperture alternately mating with selective hood openings, whereby the ducts are severally and concurrently in exclusive fluid communication with opposite hood compartments.

BACKGROUND OF INVENTIO-N The present invention generally relates to the art of combustion furnaces; more particularly, it relates to a regenerative type glass furnace and a valving apparatus for reversing the flow of combustion air and waste gases through said furnace.

A regenerative type furnace, of the type with which the present invention is concurred, has heat storage chambers (regenerators) on opposite sides of the combustion zone proper. These regenerative chambers are generally comprised of an open stacked brick array, frequently called checkers, which allows the combustion air or waste gases to pass freely through the array and provides a large surface area for heat transfer. In the operation of such furnaces, wherein one regenerative chamber has had combustion air pass therethrough and thence exit through the opposite chamber after combustion for a prescribed time period, the fluid flow in the system is reversed in such fashion that the combustion air will now enter the regenerative chamber through which the waste gases had previously passed and will exit through the opposite chamber. In this fashion, the combustion air proceeding through the checker system absorbs heat previously extracted from an exhaust gas stream and, subsequent to passing through the combustion chamber proper, will in turn dissipate its heat in the opposite checker system for most eflicient utilization of combustion heat.

The present invention is concerned with the mechanism for effecting the reversal of fluid flow through the opposed regenerative chambers. Presently, there are several known mechanisms for accomplishing this flow reversal; however, they have undesirable features. One type of known reversal 'mechanism consists essentially of a butterfly valve. This type valve leaves much to be desred in that it frequently does not make an effective seal and, consequently, detrimentally influences the thermal efliciency of the furnace system. Another drawback to the butterfly valve arrangement is the expense of maintenance, due to the involved bearing structure necessary to support the valve shaft.

Resource has also been had to various types of duct work arrangements. These arrangements are generally of two types, namely the use of two juxtaposed vertical ducts permanently aflixed to the respective canal ports leading from the regenerative chambers, or two concentrically disposed, shftable vertical duct segments which cyclically communicate with alternate canal ports. The former arrangement typically includes two air blowers, severally and permanently communicating with one othe other vertical duct segment, and a vertically movable valve disposed internally of each duct segment. Since the exhaust or waste gases are typically at a temperature of about 1200-1500 F. during contact with the internal surfaces of such valves, considerable maintenance expense is incurred in their operation because of warpage and the difficulw of maintaining a freely-operatng bearing structure. Similar maintenance expense is incurred with the latter, concentric duet arrangement, because of the complexity of mechanisms required for shifting and moving the vertically-elongated ducts into communication with the canal ports.

SUMMARY OF INVENTION In accordance with this invention, an economical valve for effecting flow reversal is provided, the valve being of relatively simple Construction and having a minimum number of moving parts, whereby its operation is substantially maintenance free.

More particularly, in accordance with this invention, there is provided a stationary housing, and two coaxial, counter-rotatable duct segments positioned on the housing, each duct having a lateral aperture which alternately mates and aligns with selective apertures, or passageways, ntegrally formed with the housing, the ducts being independently and concurrently rotatable in opposite directions by a pneumatc motor assembly.

BRIEF DESCRIPTION OF DRAWINGS The foregoing and other features of this invention will become apparent upon reference to the drawings, of which:

FIGURE 1 is a schematic end elevational view, partly in section, of a regenerative-type glass furnace including an embodiment of the reversing valve of this invention;

FIGURE 2 is an enlarged vertical sectonal view of the reversal valve illustrated in FIGURE 1;

FIGURE 3 is a schematic perspective View, partially broken away, illustrating an embodiment of this invention.

DESCRIPTION OF PREFERRED EMBODIMENT(S) Referring to the drawings, particularly to FIGURE 1, there is disclosed a crown top furnace 10 of the regenerative type and with which the apparatus of this invention finds particular utility. The furnace includes a principal firing zone 12, and a tank or chamber 14 containing a pool of molten glass 16 formed from a supply of suitable glass forming ingredients. Melting of the glass forming ingredients is accomplished by the heat produced from the combustion of gaseous or atomized fuel emanating from juxtaposed, alternately-firing nozzles 18 and 1811, the nozzles being supplied with fuel through connected inlet pipes 20 extending through the juxtaposed side walls of the furnace and being connected to the nozzles 18 and 1861.

A right-hand regeneration chamber 22 and a left hand regeneration chamber 22a are in fluid communication with melting zone 12 via a constricted burner port portion 23. The chambers 22 and 22a each extend Vertically downwardly to connect with canals 24 and 24a, respectively, on the rightand left-hand sides of FIG. l, and include an open array of brick work 32, commonly known as checkers, which serves as a heat exchanger. A wall 26 separates the canals 24 and 24a serving to aid in defining an upwardly facing opening, or port 28 in the right canal 24 and an upwardly-facing port 30 in the left canal. These ports respectively serve the purpose of allowing inlet (combustion) air or hot exhaust (waste) gases to be supplied or withdrawn from the furnace proper.

A valving apparatus, in accordance with the present invention and identified by reference numeral 32, is shown schematically in FIGURE 1 as being disposed adjacently upward of the juxtaposed ports 28 and 30. In passing, it should be mentioned that the ports may be provided with suitable dampers 34, well known in the art, for regulating fluid flow therethrough. The valving apparatus 32, as will subsequently be described, serves a simultaneous function of supplying combustion air to, and withdrawing waste gases from the furnace system.

Nozzles 18 and 18a, deployed in series along each side operate cyclcally on a timed basis. Thus, in operation, nozzle 18 on the right side of principal firing zone 12 has emanating therefrom a gaseous or atomized fuel, while left nozzle lsa is in an off position, The apparatus 32 is so controlled that combustion air is supplied through port 28 in the right canal 24 and directed up the regeneration chamber 22 where its temperature is considerably increased by passage through the hot checker system 32'. On the other hand, the waste gases (as indicated by arrows in FIG. 1) are traveling from the firing zone 12 down the left regeneration chamber 22a, dissipating heat to the left checker system, and proceeding through canal 2451 and thence up left port 30 and through apparatus 32 for atmospheric eXhaust. Thus, a considerable portion of the combustion heat is eXtracted by the stacked brick array. In the alternate cycle, the firing of left nozzle 18:: is initiated with the placing of right nozzle 18 in an off position, and the apparatus 32 being reversed to allow combustion air to enter left port 30, whereby the fluid flow in the furnace is transposed.

An embodiment of the reversing valve apparatus of this invention, identified by reference numeral 32 in FIGURE 1, is shown somewhat enlarged in FIGURE 2 and in more detail in FIGURE 3. As shown, the apparatus is Situated adjacently above the juxtaposed ports, 28 and 30 respectively, of canals 24 and 24a which lead from regeneration chambers 22 and 22a -(not shown in FIG- URES 2 and 3). The apparatus 32 is composed principally of a moveable horizontal duct assembly 36 interacting with a stationary housing member 38.

Housing member 38 essentially comprises a stationary hollow hood having a generally rectangular base 40 and including an upper portion defined by transversely opposed, longitudinal panels 44, the panels extending upwardly inward and merging with a longitudnally eX- tending, recessed semi-circular crown 46. A peripheral flange 42, or any other suitable element, is integrally formed at the hood base 40, whereby the hood may be embracingly positioned about right-hand port 28 and lefthand port 30, to completely enclose the same. In order to isolate the fluids flowing through the respective ports, the hood is provided with an interiorly-disposed, vertical partition 48, the partition being disposed intermediate the upper margin of canal separating wall 26 and the internal surface of crown 46. Partition 48 thereby defines a right internal compartment 50, exclusvely merging and fluidly communicating with right canal port 28, and a left internal compartment 52 smilarly related to left port 30.

For purposes of directing fluid flow through the respective internal compartments, and hence through the furnace itself via the opposed ports and canals, housing member 38, and more specifically, the crown 46 is provided with a plurality of selectively aligned apertures or passageways. In a preferred embodiment, the crown is pro d Wi h four c p ures o pa s g ay t o which are exclusively appurtenant to, and communicate with left internal compartment 52 and the other two of which communicate with, and are exclusively appurtenant to right compartment 50. Thus, the arcuate crown portion adjacently upward of left compartment 52 is provided with two integrally formed, longitudnally disposed passageways 52 and 54 respectively; Similarly, the crown portion adjacently upward of right compartment 50 has integral passageways 56 and 58, respectively. Furthermore, in the preferred embodiment and for reasons subsequently to become apparent, it is important that the passageways be so positioned as to define a back passageway series, 52 and 56 respectively, and a front passaway series, 54 and 58 respectively; each of said series includes a passaway exclusively communicating with one of the internal compartments and another passageway communicatng with the other compartment, both of these passageways being in transverse registry.

The horizontal duct assembly 36 includes two coaxially coupled, generally hollow cylindrical duct segments; the segments being independently and simultaneously operated, and oppositely rotatably actuated. Thus, referring to FIG. 3, the assembly includes a fluid supply duct 60 having a closed end 64 adjacently ab-utting the closed end 66 of a fluid exhaust duct 62, the ducts being maintained in coaXial alignment by a suitable coupling member, such as a bearing, or collar element 68 circumferentially disposed about the adjacently abutting closed ends. The coupling member must be of such a Construction as to allow the respective duct segments to be freely counterrotatable about their aXis.

Proximate the closed ends, fluid supply duct 60 and fluid exhaust duct 62 are each provided with a single lateral opening or aperture, 70 and 72 respectively, having geometrical configurations substantially complemental to and congruent with hood passageways 52, 54, 56 and 58 respectively. As will subsequently be described, the duct aperture-hood passageway congruency allows alternately sequential mating and alignnent, whereby fluid flow to the internal hood compartments, and hence the furnace proper, can be alternately transposed. Additionally, in order to maintain suitable fluid scaling between the hood and duct segments upon alignment of the apertures and passageways, the periphery of the respective hood passageways is provided with suitable, raised gaskets 74, such asbestos rope.

Upon positioning duct assembly 36 unto recessed crown 46, lateral aperture 70 of fluid supply duct 60 is aligned with the right front passageway 58, and lateral aperture 72 of fluid exhaust duct 62 is aligned with the left back passageway 52. Because of the engagement of the respective ducts with the raised gaskets 74, there now exists a sealed fluid path between the respective duct segments and mutually exclusive internal hood compartments. Similarly, because of the raised gasket engagement, the left front and right back passageways 54 and 56, respectively, are in efl`ect blanked out of operation by the adjacent peripheral surfaces of the ducts.

To facilitate flow transposition, each of the duct segments, due to their massiveness, is provided with a pneumatic lifting assembly 76 and a pneumatic torque producng assembly 78. The former includes opposed rollers 80, rotatably mounted above a vertcally-movable platform 82 to engage lower peripheral duct portions, and a conventional pneumatic motor 84, having suitable air supply and exhaust pipes 86, vertically driving a piston 88 rigidly fastened to the platform 82 and thereby being capable of displacing the ducts from the hood. Independent duct rotation is accomplished by the torque producing assemblies 78; the assemblies including a pivotally mounted pneumatic motor 90, having suitable air supply and exhaust pipes 92, driving a piston 94 and wing member 96. The wing members are rigidly fastened to the periphery of the respective duct segments and pivotally mounted to a bracket 98 integral with the upper margin of the piston 94; thus, in operation, the substantially vertical displacement of the respective pistons 94 transmits a tangential force component to the periphery of the ducts which, in light of the freely rotatable rollers 80 support ing the ducts, allows rotational displacement of the fluid supply duct 60 and fluid exhaust duct 62. Furthermore, to minimize the magnitude of required rotational displacement, the respective assemblies 78 are opposed in operation. That is, in any cycle the piston driving one duct segment will be driven upwardly while the piston driving the other duct segment 'will be driven downwardly, hence causing a substantially simultaneous counter-rotation of ducts 60 and 62, respectively.

Additionally, for purposes of inducing fluid flow in the system, the fluid exhaust duct 62 has its open end connected to a draft inducing source such as, for example, an exhaust fan 100 which discharges into the atmosphere through an adjacent stack 102. Supplementing this fluid flow is a complementing centrifugal blower 104 connected to the open end of the fluid supply duct 60, thereby forcing the supply fluid into the system. Keeping in mind that the ducts are to be periodically lifted (approxmately fl- /z inch) and rotated about their axis, the element connecting the exhaust fan and centrifugal blower to the respective duct segments must be of such a nature as to accommodate some reciprocal vertical movement of the ducts, as well as rotational movement. For this purpose, the element is shown as a flexible, tubular member 106 generally referred to in the arts as an elephant trunk. It will, of course, be apparent to those skilled in the art that other conventional elements may be employed, the most typical being a sliding flange connection.

With the foregoing description in mind and referring to FIGURES 1, 2 and 3 inclusively, the operation of the system is substantially as follows: as a result of exhaust fan 100 creating a negative pressure in fluid exhaust duct 62, the exhaust waste gases residing in the firing zone 12 are drawn down through left regeneration chamber 2211 into the left canal 24a and proceed to the left canal port 30, upwardly therethrough, and into the left internal hood compartment 52 where, because of the fluid communication established by the alignment of left back hood passageway 52 and lateral aperture 72, the waste gases enter exhaust duct 62 and are discharged to the atmosphere. Similarly, and contemporaneously therewith, complementing centrifugal blower 104 forces combustion air into the fluid supply duct 60 and into right internal hood compartment 50 through the aligned lateral aperture 70 and right front passageway 58, thence the air proceeds to the furnace proper through the right port, canal and regeneration chamber 28, 24 and 22, respectively. At predetermined intervals, the valve is reversed by actuating the pneumatic motors 84, which serve to vertically lift the respective duct segments approximately %1 /2 inch from the recessed crown 46, and, substantially simultaneously, pneumatic motors 90 of the torque producing assemblies 78 are actuated to independently counter-rotate fluid supply duct 60 and fluid exhaust duct 62. More speciflcally, piston 94 of the assembly connected to supply duct 60 is driven downwardly causing a clockwise rotation of the supply duct and piston 94 of the exhaust duct assembly is driven upwardly causing a counter-clockwise displacement of this duct. This simultaneous independentcounterrotation is suitably controlled to allow lateral aperture 70 of fluid supply duct 60 to come into vertical registry with left front hood passageway 54, and lateral aperture 72 of exhaust duct 62 to vertically register with right, back passageway 56. Upon repositioning the duct segments upon the recessed crown 46, the new alignment of the apertures and passageways brings the respective duct segments into fluid communication with opposite ports. In order to return the fluid communication of the ducts to the position as Originally described, fluid supply duct 60 is now rotated counter-clockwise, by its appurtenant piston being driven upwardly, and the fluid exhaust duct is rotated clockwise by a downwardly directed piston. Thus, it can be seen that sequential, alternate counter-rotation of the duct segments allows fluid communication with respectively opposed canal ports and thereby transposes fluid flow through the system in an extremely eflicient manner.

I claim:

1. A valve for reversing the flow of combustion air and waste gases in a regenerative type furnace, said furnace being characterized by a Construction including opposed regeneration chambers each having a canal leading therefrom and terminating in juxtaposed canal ports, said valve comprising: a housing enclosure adapted to em'brace each of said canal ports, an integral partiton disposed internally of said housing enclosure defining at least two compartments each of which exclusively merges with one `or the other of said canal ports, said housing enclosure having an upwardly-facing recessed crown and including first, second, third and fourth passageways integrally formed within said crown, said first and second passageways being axially disposed and exclusively communicatng with one of said compartments and said third a d fourth passageways being axially disposed and exclusively communicatng with the other of said compartments; first and second coaxially coupled independently-rotata'ble duct segments nesting with said recessed crown, said first duct segment nesting proximate said first and third passage-ways having a lateral aperture mating with said first passageway and said second duct segment nesting proximate said second and fourth passageways having a lateral aperture mating with said fourth passageway; exhausting means coupled to said first duct segment for Withdrawing waste gases therefrom and blower means coupled to said second duct segment for supplying air thereto; means engaging said duct segments for relatively displacng said segments and said housing enclosure at predetermined intervals, and means aflixed to said duct segments for counter-rotating said duct segments substantially simultaneously with said displacement, whereby said first duct segment aperture is aligned -with said third passageway and said second duct segment aperture is aligned with said second passageway, the flow of combustion air and waste gases through said furnace thereby being transposed.

2. A valving apparatus for reversing fluid flow through juxtaposed ports comprising: a hood positioned about said ports having at least two pairs of integrally-formed, longitudinally-disposed passageways, each of said pairs having a first passageway exclusively communicatng with one of said ports and a second passageway exclusively communicatng -with another of said ports; a fluid supply duct movably mounted on said hood adjacent one of said passageway pairs and having a lateral aperture aligned with the first passageway of said pair, a fluid exhaust duct movably mounted on said hood adjacent the other of said passage- Way pairs and having a lateral aperture aligned with the second passageway of said pair, said ducts thereby being in fluid communication with opposite ports; means connected to said fluid supply duct and said fluid exhaust duct for independently and substantially simultaneously transposing the alignment of the respective lateral apertures with said first and second passageways of the respective passageway pars.

3. A valving apparatus for reversing fluid flow through juxtaposed ports comprising: a hood positioned about said ports having at least two pairs of integrally-formed, longitudinally-disposed passageways, each of said pairs having a first passageway exclusively communicatng with one of said ports and a second passageway exclusively communicatng with another of said ports; a fluid supply duct movably mounted on said hood adjacent o-ne of said passageway pairs and having a lateral aperture aligned with the first passageway of said pair, a fluid exhaust duct movably mounted on said hood adjacent the other of said passageway pairs and having a lateral aperture aligned with &495514 7 8 the second passageway of said pair, said ducts thereby -be- References Cited ing in fluid communication With opposite ports; means connected to said fluid supply duct and said fluid exhaust UNITED STATES PATENTS duct for transposing the alignment of the respective lateral 70,` 965 K efer 137-3 09 XR apertu'es with said first and second passageways of the 5 3,349,791 10/ 1967 Guzman et al 137-309 respective passageway pairs.

4. The valving apparatus of claim 3 wherein said fluid WILLIAM F. O`DEA, Primary Examiner ly duct and sad flud exhaust duct are coaxally cou- RICHARD GERARD, Assistant Examiner 5. The valvng apparatus of claim 4 wherein the pas- 10 sageways comprising said pairs are in t'ansverse registry.

6. The valving apparatus of claim 5 wherein said first 137-616.7; 263-15 passageway of each of said pairs and said second passageway of each of said pairs are in longitudinal registry.

U.S. Cl. X.R. 

